STDU Viewer is a free viewer for multiple file formats. The goal of this software is to replace the multiple document viewers with a single one simple application. STDU Viewer supports TIFF, PDF, DjVu, XPS, JBIG2, WWF document formats. These are the most popular formats for scientific and technical documentation.

Note: This program is advertising supported and may offer
to install third party programs that are not required.
These may include a toolbar, changing your homepage,
default search engine or installing other party programs.
Please watch the installation carefully to opt out.